In an LTE system, a control area of a physical downlink control channel (Physical Downlink Control Channel, hereinafter briefly referred to as PDCCH) is formed by a control channel element (Control Channel Element, hereinafter briefly referred to as CCE) obtained through logic division, where the mapping of the CCE to a resource element (Resource Element, hereinafter briefly referred to as RE) adopts a complete interleaving manner. The transmission of downlink control information (Downlink Control Information, hereinafter briefly referred to as DCI) is also based on a unit of CCE. One piece of DCI for one user equipment (User Equipment, hereinafter briefly referred to as UE) may be sent in N consecutive CCEs, and possible values of N in the LTE system are 1, 2, 4, and 8, which are called aggregation levels of the CCE. The UE performs blind detection on the PDCCH in the control area, and searches to determine whether a PDCCH that is sent for the UE exists. The blind detection refers to that decoding is attempted on different DCI formats and CCE aggregation levels by using a radio network temporary identity (Radio Network Temporary Identity, hereinafter briefly referred to as RNTI) of the UE, and if the decoding is correct, the DCI for the UE is received. By performing blind detection, a specific time-frequency resource location of each PDCCH is determined, thereby implementing receiving of the PDCCH, reading of high-layer signaling scheduling information such as system information, and receiving of corresponding information. The current protocol specifies the times that blind detection is performed on PDCCHs of different aggregation levels, and this specification ensures that the times that blind detection is performed on the PDCCH by the UE do not exceed the maximum the times that blind detection is performed.
To improve system performance and expand capacity of a physical downlink control channel (Physical Downlink Control, hereinafter briefly referred to as PDCCH), an enhanced physical downlink control channel (enhanced Physical Downlink Control Channel, hereinafter briefly referred to as E-PDCCH) is introduced in the R11 version. The E-PDCCH has two transmission modes, namely, localized transmission (Localized) with a consecutive frequency domain, and distributed transmission (Distributed) with a discrete frequency domain, which are applied to different scenarios. Generally, the localized transmission mode is mostly used in a scenario in which a base station can obtain more precise channel information fed back by the UE, and interference of a neighboring cell is not very intensive with the change of a subframe, and in this case, the base station selects, according to the CSI fed back by the UE, consecutive frequency resources with better quality to transmit the E-PDCCH for the terminal, and performs precoding/beam forming processing to improve the transmission performance. In a scenario in which the channel information cannot be obtained accurately, or the interference of the neighboring cell is intensive with the change of the subframe and is unpredictable, the distributed manner needs to be used for transmitting the E-PDCCH, namely, discrete frequency resources are used for transmission, thereby obtaining a diversity gain.
In the prior art, the UE needs to perform blind detection on signaling borne by the E-PDCCH, so as to receive the E-PDCCH that is sent for the UE. The detection on the E-PDCCH likewise needs to satisfy the requirement of not exceeding the maximum number of times that blind detection is performed. The number of times that blind detection is performed corresponds to the number of physical control channel candidates, and therefore when the number of physical control channel candidates is determined, the number of times that blind detection is performed is determined. However, in some cases, the UE is configured to detect an E-DPCCH of a localized mapping manner and an E-DPCCH of a distributed mapping manner at the same time. In this implementation scenario, if the UE detects the E-DPCCHs of the two manners, it may be caused that the number of times that blind detection is performed exceeds the maximum the times that blind detection is performed, thereby causing a long blind detection time of the UE, and influencing processing of other service data of the UE.